This application is for partial funding of a symposium 'Skeletal muscle - crossbridges' that forms part of the XXXII International Congress of Physiological Sciences, Glasgow, August 1-5, 1993. This congress is organized as a series of Symposia with strong themes that run throughout the meeting. Chairpersons and organizers for each symposium have been selected because of their contributions to the symposium theme. The list of speakers includes major contributors in the several exciting developments that are presently occurring in skeletal muscle research. Two of the contributions will set these developments into the context of existing knowledge (H.E. Huxley, Simmons). These new developments arise principally out of: 1) atomic resolution structures of actin and myosin, 2) time resolved structural changes of crossbridges especially from low angle X-ray diffraction and freeze-substitution electron microscopy. These advances in turn depend in part on the novel mechanical techniques developed by Lombardi and co-workers. 3) in vitro motility and force measurements of individual myosin and actin filaments. These are techniques that permit individual cross-bridge events to be analyzed. They also permit insights afforded by molecular genetics to be fully exploited in muscle research. This meeting is timely and sets an exciting stage for the other muscle related symposia of the meeting. In this the meeting is unique. It allows and encourages the advances made in skeletal muscle research (where the highly organized sarcomer structure makes this muscle amenable to advanced biophysical techniques) to be transmitted in a direct way to other muscle researchers. In this way it complements the more traditionally interactive meetings on skeletal muscle (such as The Contractility Gordon Conference, also in 1993) where nearly all the participants are expert in one particular area of muscle research. Anticipated attendance is expected to be between 5000 and 6000, ensuring exposure to a wide range of both basic and clinical scientists involved in muscle physiology. The importance of this symposium is that it launches the exciting developments and results of the past three years in skeletal muscle into the general awareness of a much wider body of scientists. This knowledge will percolate in a broad way into research on health related muscle disease and dysfunction.